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l ,Nrrsn \VILLIAM GRIFFITH, OF PITTSBURG, PENNSYLVANIA, ASSIGIOR TO HIM- SELF AND JAMES C. GRAY, OF SAME PLACE.

PROCESS OF P UR|FYING MOLTEN IRON.

SPECIFICATION forming part of Letters Patent No. 289,089, dated November 37, 1883. A pplicntion filed May 25, 1883. (No specimens.)

To all whom it may concern.- v

Be it known that I, WIL'I. GIuFFifH, of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Processes for Puri-- fying Molten ,Iron; and I do hereby declare the following to be a full, clear, and exact de scription thereof.

- My invention relates to an improvement in the manufacture of iron and steel; and it consists in treating the molten metal with carbonate of potassium and nitrate of sodium in order to refine it and to remove impurities therefrom. These chemicals may be added or introduced into the-molten metal after it has been run from the furnace into the ladle or mold, or they may be added to the metal in Bessemer converters, puddling, refining, openhearth, cupola,-blast, and other furnaces.

' fore it comes to nature.

p I will now describe my invention, so that. others skilled in the art may use the same. Whenthe metal has been reduced to a molten state in the furnace, carbonate of potassium and nitrate ofsodium-equal parts of each-are added thereto. These unite with the impurities and rise. to the surface with the slag, leaving the refined and purified metal free .to be drawn from the furnace; In the paddling-furnace the chemicals should be added. to the metal while it is still boiling and be- ,In order that the chemicals may act properly, care should be taken to place them beneaththe surface of the molten metal. This may be easilyhccomplishcd byinclosing them in thin metal cases or boxes.

Instead of introducing the carbonate of po.- I

' tassium and nitrate of sodiumeinto the fur- .with each ton of metal.

The advantages of my invention are that the phosphorus and other foreign substances are removed from the metal, and it is there'- fore tough and fibrous throughout, and a superior quality of manufactured iron or steel may be produced from an inferior quality 'of metal.

I amaware that carbonate of potassium and 'nitrate of sodium have been employed separately and each in conjunction with other chemicals in physics for purifying iron and steel, and do not broadly claim the same; but

I am not aware that said two ingredients have alone composed a compound employed, n manner as hereiubefore specified, and, therefore Having thus described myiuvention, what l. claim, and desire to secure by Letters Patent, 1s 4 5 l 1 .The process herein] described for refining and purifying iron and steel, which consists in subjecting the molten metal to the action of a compound composed of the two ingredients, carbonate of potassium and nitrate of sodium, in substantially the proportions specified, asand for the purposes specified.

In testimony whereof I have hereunto set my hand thislllth day of May, A. D. 1883. WILLIAM GRIFFITH.

Witnesses: a

W. B. CoRWI'N', J. K. BAKEWELL. 

